External noise Lps Crown 1500

Hi wanted to make a technical consultation, buy a crown power lps 1500, and it turns out from the start of the fan noise also makes a small continuous high-pitched noise similar to issuing a "cricket" but much softer. like something electrical or something, this is in the hardware of the stage that noise does not play through the speakers. is this normal?? blocked or there will come? thanks greetings.